Q: Radishes - what did I do wrong? I had beautiful strong healthy huge leafy tops and hardly any roots at all. If I plant the rest of of my radish seeds, when should I do it for best radish quality? Also do they need full sun? How much watering? (I watered religiously every night, was it too much?)
A: There are two possibilities why your radishes produced tops and not bulbs.
- The radishes may have been planted too closely and needed thinning. If radishes are overcrowded they don't have the space they need to produce nice-sized, fleshy bulbs. Radishes like to be thinned to two inches apart for optimal bulb formation.
- There may be too much nitrogen in your soil (from compost, manure, or other nitrogen fertilizer). The excess nitrogen will encourage vigorous plant growth of the radish tops with very little bulb growth. If you have a healthy soil, you probably don't need to add nitrogen to your soil when you plant your radish seed.
The best time to plant radishes is in the early to mid-spring and again in the early fall for good radish quality. Radishes like cooler soil conditions and less heat-degree-hours (the hours of sunlight each day). When the soil starts to heat up and the days get longer, radishes become hotter in flavor, develop a woody texture, and the plants will bolt to seed sooner.